"""
Opens links in a browser.

Installation
------------

First use case: local use
~~~~~~~~~~~~~~~~~~~~~~~~~
If you use poezio on your workstation, this is for you.
You only have to load the plugin: ::

    /load link

Second use case: remote use
~~~~~~~~~~~~~~~~~~~~~~~~~~~
If you use poezio through SSH, this is for you.

.. note:: Small explanation: Poezio will create a `Unix FIFO`_ and send the commands in,
            and you will have to run a dæmon locally with ssh, to get those commands.

First, set the :term:`exec_remote` option in the config file to ``true``. Then select
the directory you want to put the fifo in (default is the current
directory, :file:`./`), the :file:`poezio.fifo` file will be created there.

After that, load the plugin: ::

    /load link

And open a link with :term:`/link` (as described below), this will create the FIFO.

You need to grab poezio’s sources on your client computer, or at least the `daemon.py`_
file.

Finally, on your client computer, run the ssh command:

.. code-block:: bash

    ssh toto@example.org "cat ~/poezio/poezio.fifo" | python3 daemon.py

Usage
-----

.. glossary::

    /link
        **Usage:** ``/link [range] [command]``

        This plugin adds a :term:`/link` command that will open the links in
        ``firefox``. If you want to use another browser, or any other
        command, you can use the :term:`/set` command to change the
        :term:`browser` option. You can also specify the command to execute
        directly in the arguments.  For example `/link "mpv %s"` will open
        the first link found using mpv, instead of the configured browser.


        :term:`/link` without argument will open the last link found
        in the current tab, if any is found. An optional range
        argument can be given, to select one or more links to
        open. Examples:
        ``/link 1`` is equivalent to ``/link``
        ``/link 3`` will open the third link found in the current tab,
        starting from the bottom.
        ``/link 1:5`` will open the last five links in the current tab
        ``/link :2`` will open the last two links

Options
-------

:term:`exec_remote`

    To execute the command on your client

.. glossary::

    browser
        Set the default browser started by the plugin

.. _Unix FIFO: https://en.wikipedia.org/wiki/Named_pipe
.. _daemon.py: https://lab.louiz.org/poezio/poezio/raw/master/poezio/daemon.py

"""
import platform
import re

from poezio.plugin import BasePlugin
from poezio.xhtml import clean_text
from poezio import common
from poezio import tabs

url_pattern = re.compile(r'\b(?:http[s]?://(?:\S+))|(?:magnet:\?(?:\S+))\b',
                         re.I | re.U)
app_mapping = {
    'Linux': 'xdg-open',
    'Darwin': 'open',
}


class Plugin(BasePlugin):
    def init(self):
        for _class in (tabs.MucTab, tabs.PrivateTab, tabs.DynamicConversationTab, tabs.StaticConversationTab):
            self.api.add_tab_command(
                _class,
                'link',
                self.command_link,
                usage='[num] [command]',
                help=
                'Opens the last link from the conversation into a browser.\n\
                    If [num] is given, then it will\open the num-th link displayed. \
                    Use a [command] argument to override the configured browser value.',
                short='Open links into a browser')

    def find_link(self, nb):
        messages = self.api.get_conversation_messages()
        if not messages:
            return None
        for message in messages[::-1]:
            matches = url_pattern.findall(clean_text(message.txt))
            if matches:
                for url in matches[::-1]:
                    if nb == 1:
                        return url
                    else:
                        nb -= 1
        return None

    def command_link(self, args):
        args = common.shell_split(args)
        start = 1
        end = 1
        # With two arguments, the first is the range, the second is the command
        # With only one argument, it is a range if it starts with a number
        # or :, otherwise it is a command
        if len(args) == 2 or\
           len(args) == 1 and (args[0][0].isnumeric() or args[0][0] == ":"):
            if args[0].find(':') == -1:
                try:
                    start = int(args[0])
                    end = start
                except ValueError:
                    return self.api.run_command('/help link')
            else:
                start, end = args[0].split(':', 1)
                if start == '':
                    start = 1
                try:
                    start = int(start)
                    end = int(end)
                except ValueError:
                    return self.api.information(
                        'Invalid range: %s' % (args[0]), 'Error')
        command = None
        if len(args) == 2:
            command = args[1]
        if len(args) == 1 and (not args[0][0].isnumeric()
                               and args[0][0] != ":"):
            command = args[0]
        for nb in range(start, end + 1):
            link = self.find_link(nb)
            if not link:
                return self.api.information('No URL found.', 'Warning')
            default = app_mapping.get(platform.system(), 'firefox')
            if command is None:
                self.core.exec_command(
                    [self.config.get('browser', default), link])
            else:
                self.core.exec_command([command, link])

    def cleanup(self):
        del self.config
